1. Technical Field
This invention relates generally to drug delivery systems, and more particularly to a centrally managed system with multiple infusion pumps that provide a patient with metered doses of various intravenous medications.
2. Background Information
A centrally managed, multipump, drug infusion system alleviates many concerns in such environments as intensive care units, cardiac units, operating rooms, and trauma centers. Capable of infusing several drugs simultaneously, and of doing so at different points of the body in a manner accommodating incompatible drugs, the system provides an organized complement of components suited for use under crisis conditions.
One such system includes a microprocessor-based central management unit mounted together with infusion pump modules on an IV stand. The central management unit controls the internal setup of the pump modules to cause them to function as desired. In addition, it receives and displays information from the pump modules on a touch screen that also serves as an input device with which the user can enter data and commands to the central management unit.
Aligned light-emitting diodes and phototransistors mounted on a bezel surrounding the screen provide a grid pattern of light beams which, when interrupted by the user's finger touching the screen, trigger selected control functions of the central management unit. The central management unit displays a menu of various commands or parameters, and the user simply points at the command or parameter selected. This interrupts a light beam, and the microprocessor thereafter performs accordingly.
Operation typically proceeds in one of two ways. In what may be called dosage-based operation, the physician specifies a dosage to be administered, with operation involving calculation of the corresponding infusion rate so that the infusion pump module can be controlled accordingly. In rate-based operation, however, there is no need to calculate the rate because it is specified. Instead, rate-based operation involves calculation of the corresponding dosage, this being done so that a record may be kept of the dosage that is administered.
In either case, a calculation must be made, and it is therefore desirable that the system include some means for doing this in a manner suited to crisis conditions. The calculation procedure should be quick and convenient with little chance for user confusion and error, and it should facilitate medication adjustments according to patient reaction.
Although calculators exist, they are not configured for this special function. With some calculators, for example, the specified dosage or infusion rate must be entered along with other necessary parameter values. Then, the solution (infusion rate or dosage) is displayed, and this value must be transferred to the corresponding infusion pump module, the process taking time and effort and risking error.
Furthermore, data for one infusion pump module is often lost when the calculator is used for another infusion pump module, and this compounds the problem. In addition, it is sometimes desirable to perform dose and infusion rate calculations during titration procedures, and existing calculator arrangements are inconvenient to use for this purpose. Consequently, it is desirable to have a system with a calculator function that overcomes these concerns.